Type positioning mechanism



Oct. 16, 1956 L. s. WILLIAMS TYPE POSITIONING MECHANISM 3 Sheets-Sheet 1Filed Feb. 15', 1956 INVENTOR.

ATTOR/VYS Filed Feb. 15, 1956 Oct. 16, 1956 s w Ms 2,766,687

TYPE POSITIONING MECHANISM 3' Sheets-Sheet 2 INVENTOR.

l V/LL/AMS ATTORNEYS Oct. 16, 1956 L. s. WILLIAMS 2,766,687

TYPE POSITIONING MECHANISM Filed Feb. 15, 1956 3 Sheets-Sheet 3INVENTOR.

LAWREA/Cg; 3., W/LLMMS ATTORNEYS Unite States atent O TYPE POSITIONINGMECHANISM Lawrence S. Williams, Toledo, Ohio, assiguor to Toledo lSicaleCompany, Toledo, Ohio, a corporation of New ersey Application February15, 1956, Serial No. 565,677

' Claims. 01. 101-99 This invention relates to printing devices and inparticular to means for positioning a plurality of type-bearing wheelsin a printing station.

The principal object of this invention is to provide means foraccurately rotating type wheels into printing position.

Another object of the invention is to provide spring means for returningthe type wheels to their original positions at the end of a printingoperation.

A further object of the invention is to provide means for aligning thetype wheels in their printing positions, which aligning means alsoprevents movement of the type wheels during the printing operation.

Other objects and advantages will be apparent from the followingdescription in which reference is had to the accompanying drawings.

According to the invention, a plurality of type wheels 1 are operativelyconnected to columns of keys on a keyboard. Depression of a selected keyin each column rotates the type wheels to move the wheels to positionscorresponding to the keys depressed. Each wheel has printing charactersaround half of its periphery and is notched on its other half, therebeing a notch for each printing character. After the type has been setup by the keys, a handle is operated and causes centering means toengage one notch of each wheel to correctly align the Wheels and preventtheir movement during the printing operation. At the end of the printingcycle, the centering means disengages from the notches in the wheels andthe wheels are returned by the spring means to their original positions.

In the drawings:

Figure I is a view in side elevation of a printing weighing scaleembodying the invention.

Figure II is an enlarged view, partly in section, of the keyboard andtype wheels shown in Figure I.

Figure III is a fragmentary view taken substantially along line III-IIIof Figure II.

Figure IV is an oblique view of one of the type wheels illustrating thespring means for returning the type wheel to its original position withrespect to its axle at the end of a printing cycle.

Figure V is an enlarged view taken substantially along line V-V ofFigure II, parts being broken away and parts shown in section.

Figure VI is an elevational view of a modified centering means which maybe substituted for the centering bar structure shown in Figure III.

Figure VII is an enlarged perspective view of the centering means shownin Figure VI.

These specific figures and the accompanying description are intendedmerely to illustrate the invention but not to limit its scope.

A printing weighing scale 1 embodying the invention comprises a base 2and a housing 3 surmounting a rear portion of the base. A platter 4 isoperatively connected to a disk chart 5 by means of automatic loadcounter"-- balancing mechanism (not shown) located'withiir'the' PatentedOct. 16, 1956 ice housing 3. The chart 5, in response to loads placedupon the platter 4, moves raised printing characters carried on amarginal area of the chart into a printing station. The raised printingcharacters on chart 5 correspond respectively to the weights of variousloads placed upon the platter 4.

A price ring 6 lying in a plane which is angular with respect to theplane of the chart 5 has raised printing characters on a beveled facewhich characters correspond respectively to selected prices per pound atwhich articles being weighed on the platter 4 are to be sold.

Aplurality of adjacent type wheels 7 lie in parallel planes which areperpendicular to the plane of the chart 5. Each of the type wheels isindividually operable in response to depression of a key 8 mounted on akeyboard 9. The keys 8 are operatively connected to the typewheels 7 bymeans of cords 10, one for each type wheel 7. The weighing scale has acomputing cylinder chart of well known construction (not shown) mountedcoaxially with the chart 5. When the value of an article on the platter4 computed at a previously set up price is indicated to the operator inthe well known manner, he depresses selected ones of the keys 8 to setup the indicated value of the article on the type wheels 7. An imprintof the weight, price, and value of the article on the platter v4 thenmay be recorded on a ticket 11, which upon pivotal movement of a handle12 moves into juxtaposition with the printing characters on the wheels7, price ring 6, and chart 1 where an imprint may be made upon theticket 11 by printing mechanism (not shown).

Referring now to Figure II, the type wheels 7 are journaled on bushings13, the bushings in turned being sleeved over an axle 14. The axle 14 isthreaded at both ends to receive a pair of nuts 15 which act to clampthe bushings together on the axle. The bushings cannot rotate on theaxle 14 because of their being clamped by the nuts 15. Rotation of thewheels 7 is therefore around the bushings. A pair of arms 16 is engagedaround the opposite ends of the axle 14 outside the nuts 15. The axle 14is clamped with respect to the arms 16 by means of nuts 17 on the outerends of the axle.

Rotation of the type wheels 7 is brought about by depression of the keys8, which keys are operatively connected to pivotal arms 18. Depressionof selected keys causes the pivotal arms to pull on the cords 10 whichare wrapped more than halfway around hub-like shoulders 19 on the typewheels 7. Pivotal movement of an arm 18 therefore causes the type wheeloperatively connected to that arm to be rotated to set up in printingposition a type character corresponding to the key 8 which wasdepressed.

Referring to Figure III, a link 20 is adapted to be pulled downwardlywhen the handle 12 is operated. A stirrup 21 is resiliently connected tothe upper end of the link 20 by means of a spring 22. The stirrup isconnected to a radially extending arm 23 fixed to a pivotal shaft 24 onwhich are carried guides 25 for the cords 10. When the link 20 is pulleddownwardly as the arm 23 is operated (from the position shown in dottedlines to the position shown in solid lines in Figure III) the stirrup 21rocks the arm 23 on the shaft 24 and causes a pair of arms 26 to rockalso. A centering bar 27 mounted between the arms 26 engages in certainof a series of notches 28 which extend around approximately one half ofthe periphery of each of the type wheels 7. When the printing operationtakes place in response to operation of the handle 12, the wheels 7 areprevented from rotating on the bushings 13 by the centering bar 27engaging a notch of each wheel 7. The spring 22 is provided to preventdamage by the centering bar 27 to the wheels 7 when the link 20overtravels.

'Each typewheel 7'has' a spiral spring 29 enclosed in a recess in thetype wheel with one of its end connected to the bushing 13 and the otherend connected to the type wheel. The springs are provided to resilientlyurge the wheels toward their original positions to maintain the cords 10under tension. Thus, except when held by the centering bar 27, the wheelpositions always correspond with the depressed keys.

Referring now to Figure V, the keys 3 on the keyboard 9 in four columns.One column is provided for each type wheel 7. Bars 30 mounted in thekeyboard 9 are adapted to be operated by the keys in the columnoverlying the bar. Depression of a key will pivot its bar on an axisparallel to its length through an arc corresponding to the key selected.The arm 18, fixed to the bar, pulls on the cord 10 connected to the armand thereby rotates the type wheel on the opposite end of the cordaccording to the key depressed. The bars 30 are urged toward the keys bymeans of springs 31. When the keys are depressed, latch bars 32, one foreach column of keys, catches a collar 33 on each depressed key to holdthem down until a latch releasing arm 34 operatively connected, by meansof a cord 35, to printing mechanism which in turn is driven by thehandle 12. releases all of the depressed keys. The latch bars 32 areurged toward the keys with which they cooperate by means of springs 36,one for each bar 32.

To prevent damage to the cords 10 should the keys be punched with toomuch force, a tension spring 37 is inserted between each cord 10 and thecorresponding arm 18 so that the sudden impacts will be absorbed by thesprings 37. If such springs were not provided and a key was punched toohard, its wheel would spin beyond the selected position. Although itwould return to the selected position after having passed it, theovershooting of the wheels could cause damage to the spiral spring 29and the cords 10.

In operation, when the value of an article on the platter 4 has beendetermined, proper keys 8 are punched by the operator to set up the typeon the wheels 7 sov that the value of the article will be printed onthe. ticket 11 along with the weight and the price at which the articlesells. One key in each column is. depressed. The depressed keys are heldin such depressed positions by the latch bars 32 until the handle 12 isoperated and the centering bar 27 engages in the notches 28 to align andlock the wheels 7. After the centering bar, has been engaged, the cord35 operates the latch releasing arm 34 to cause. the. latch ba s 32 torelease the collars: 33 and return the keys to their non-depressedpositions. by means of springs 38 around the keys.v The wheels remain,held; in position by the centering bar 27 until an imprint of thecharacters has been made upon. the ticket 11. When the latch releasingarm 34- causes the keys. 8 to be released, the bars 30 are urged; totheir original positions by the springs 31. This may cause the'arrns 18to create a small amount of; slack in the cords; 10. Shrouds 39 preventthe cords from slipping from, the pulleys around which they pass whenthere slack the cords.

When the handle 12 is returned to its; original position, the centeringbar 27 releases the wheels. 7, and the spiral springs 29 return thewheels to their original posi.-- tions. The slack in the cables is takenup. when. the wheels return to their non-operated positions. An im:print has now been made on the ticket 11 of the weight, price, and valueof the article on the platter 4; and the scale is ready for subsequentoperations.

The centering bar 27 is a satisfactory means for al ign. ing orcentering the type wheels 7 in their printing positions; and forpreventing movement of the type wheels during the printing operationwhen the notches 28& in in the type wheels are of the same size anddepth andwhen the type wheel axle 14 s paralle t h h f about the axis,of which the, centering bar 2,7 is ta ked.

are arranged However, when the notches 28 in the type wheels 7 are ofdifferent sizes and depths and/or the axes of the axle 14 and of theshaft 24 are not parallel, as may occur in mass productionmanufacturing, it is impossible for the centering bar to align the typewheels so that they may print a straight line of numerals. That is, thesingle pawl finger on the centering bar 27 cannot perfectly align thenotches on four separate wheels. unless the bottoms of four equallysized notches extend in a straight line that is parallel to the singlepawl finger.

A modified centering means which is illustrated in Figures VI and VIImay be substituted for the centering bar 27. The modified centeringmeans provides automatic compensation for different depths in thenotches 28 in the type wheels 7 and is adjustable to accommodatenon-parallel axle 14 and shaft 24 axes.

The modified centering means includes a bell crank 40 having an arm 41,which corresponds exactly in structure and function to the arm 23herei'nbefore described, and a pair of arms 42 which corresponds to thepair of arms 26 hereinbefore described. When the bell crank 40 issubstituted for the centering bar structure, which includes said arms 23and 26, the stirrup 21 is. pivotally connected in a hole 43 in the arm41 of the bell crank 40 and the shaft 24 is located in a pair of holes44 in the bell crank 40.

The pair of. arms 42 of the bell crank 40. are spaced apart by anintegrally formed body portion 45 upon which are mounted four springpawls 46, there being an individual pawl 46 for each of the type wheels7. Each of the spring pawls 46 has a notched end 47, a typewheel-centering finger 48, a slot 49,, and a bent end 50. Screws 51, onefor each of the pawls 46, extend through the body portion 45 of the bellcrank 40 and through notches in the notched ends 47 of the pawls and arethreaded into an elongated nut 52 which is common to all of the. screws.The nut 52 presses all of the notched ends 47 of the pawls 46 againstthe body portion 45. of the bell crank and holds the pawls in place.Pivotal movement of the pawls 46 about the axes of the screws 51 islimited by means of pins 53 that are mounted on the body portion 45 ofthe bell crank and that protrude through the slots 49 in the pawls. Onlythe, notched ends 47 of the spring pawls 46 are fixed in; place so thatthe bent ends 50 of the pawls are free resiliently to: move back andforth toward or away from the body portion 45. of the bell crank 40, thebody portion 45 being recessed beyond the point where the nut 52 holdsthe pawls 46 to permit such movement When the bell crank 49 is rockedtoward the type wheels 7, the fingers 48 on the individual spring pawls46 engage notches 23 in the ty-pe wheels. The fingers 48, because of theresiliency of the pawls 46' and because of the manner in which the pawlsare mounted, automatically find the bottoms of their respective notches,any finger which happens to find a shallow or small notch being bentback toward the recessed body portion. 45 of the bell crank 40. Thefingers 48 on the pawls align or center the type wheels 7 in theirprinting positions and prevent movement of the type wheels during theprinting operation. The modified centering meanscauses the typewheels 7to print a straight line of numerals eventhough. the notches 28 are ofvarious sizesand depths. Hence, close tolerance in the forming of thenotches 28 in the type wheels 7 is not necessary.

Another important feature of the modified centering means, whichincludes the individual spring pawls 46,

' is the fact that each spring pawl is individually adjustable toaccommodate non-parallel axle l4 and shaft 24 axes. The single pawlfinger on the centering bar 27' cannot perfectly align the notches inaplnrality of separate wheels unless the bottoms of the notches extendin a straight line. that is parallel to the single pawl finger. I n .themodified structure, if after assembly in the fac tory or after servicingin the field, the type wheels 7 do not print a straight line of numeralsbecause of a nonparallel relationship between the axes of the axle 14and the shaft 24, any one or all of the screws 51 may be slightlyloosened and any one or all of the pawls 46 there after may be shiftedtoward or away from the screws 51. The pawls 46 may be manually shiftedby grasping their bent ends 50 with a pair of pliers. The exact locationof the pawls 46 is determined by trial and error printing until the typewheels 7 print in a straight line.

There is thus provided centering means having an individual pawl foreach of the type wheels 7 which individual pawl resiliently andautomatically finds the bottom of the notch in the wheel matedtherewith, thus, automatically compensating for ditferent sizes anddepths in the notches in the wheel, and which individual pawl isadjustable relative to every other pawl in the centering means toaccommodate non-parallel axle 14 and shaft 24 axes.

The embodiments of the invention herein shown and described are to beregarded as illustrative only, and it is to be understood that theinvention is susceptible to variation, modification, and change withinthe spirit and scope of the subjoined claims.

This application is a continuation-in-part of application Serial No.328,551, filed December 30, 1952 and now abandoned.

Having described the invention, I claim:

1. In a type positioning device, in combination, a keyboard, a pluralityof columns of keys on said keyboard, a plurality of type wheelsrotatable on an axle and each having a series of raised printing typeand a series of notches positioned with respect to the raised printingtype, a cord drive operatively connecting each wheel to a column ofkeys, the keys of each column being adapted to selectively position thecooperating wheel to an approximate printing position, and centeringmeans adapted to engage one of the plurality of notches on each wheel toaccurately align the wheels during a printing operation.

2. A device according to claim 1 in which each wheel is connected to itsmounting by means of a multiple-turn spiral spring.

3. In a type positioning device, in combination, a keyboard, at leastone column of depressible keys on said keyboard, at least onetype-bearing, pulley-like wheel having a series of raised printing typeand a series of notches positioned with respect to the raised printingtype, the wheel having a laterally extending hub, a cord attached to thewheel and wrapped around the hub for operatively connecting the wheel tothe keys, depression of a selected key rotating the wheel through thecord to present selected type on the wheel in an approximate printingposition, and centering means adapted to engage one of the plurality ofnotches on the wheel to accurately align the wheel during a printingoperation, said centering means being released after an impression ofthe type has been taken.

4. In a device adapted to move type into printing position, incombination, a keyboard, a plurality of columns of keys on saidkeyboard, a plurality of type-bearing, pulley-like wheels each having aseries of raised printing type and a series of notches positioned withrespect to the raised printing type, each wheel having a laterallyextending hub, an axle on which the wheels are rotatably mounted, saidwheels lying in adjacent parallel planes, a cord attached to each wheeland wrapped around its hub for operatively connecting each wheel to acolumn of keys, depression of a key rotating the wheel operativelyconnected to its column to present type in an approximate printingstation, and centering means adapted to engage one of the plurality ofnotches on each wheel to finally align the wheels during a printingoperation.

5. A device according to claim 4 in which each wheel is connected to theaxle by means of a multiple-turn spiral spring.

No references cited.

